fix(role): compute <output> accessible name from labels

[pavelfeldman]

Fixes: #27403

[github-actions]

Test results for "tests 1"

1 failed
❌ [playwright-test] › loader.spec.ts:755:5 › should resolve .js import to .tsx file in non-ESM mode for components

8 flaky

⚠️ [chromium] › page/page-event-request.spec.ts:101:3 › should report navigation requests and responses handled by service worker
⚠️ [firefox] › library/trace-viewer.spec.ts:680:1 › should follow redirects
⚠️ [firefox] › library/tracing.spec.ts:239:5 › should not include trace resources from the previous chunks
⚠️ [chromium] › library/tracing.spec.ts:239:5 › should not include trace resources from the previous chunks
⚠️ [playwright-test] › ui-mode-test-progress.spec.ts:167:5 › should update tracing network live
⚠️ [webkit] › library/browsercontext-reuse.spec.ts:50:1 › should reset serviceworker
⚠️ [webkit] › library/tracing.spec.ts:239:5 › should not include trace resources from the previous chunks
⚠️ [webkit] › page/page-goto.spec.ts:266:3 › should fail when navigating to bad SSL

25789 passed, 605 skipped
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Merge workflow run.